Power case for electronic device

ABSTRACT

A protective case for an electronic device includes a cover, a rechargeable battery, first and second electrical connectors, and electrical circuitry. The first electrical connector is accessible at an outer surface of the cover for electrically connecting to an external power source. The second electrical connector is accessible at an inner surface of the cover for electrically connecting the protective case to the electronic device. The electrical circuitry distributes the received electrical power to the electronic device and to the rechargeable battery. The electrical circuitry also distributes stored electrical power from the rechargeable battery to the electronic device. Distribution of the stored electrical power to the electronic device is conditioned upon an input received from the electronic device, a mode of the protective case, and or a signal received at the protective case.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/833,257, filed on Aug. 24, 2015, which is a continuation of U.S.patent application Ser. No. 14/524,081, filed Oct. 27, 2014, which is acontinuation of U.S. patent application Ser. No. 13/839,415, filed Mar.15, 2013, now U.S. Pat. No. 8,910,863, which claims the benefit of U.S.Provisional Application 61/749,313, filed Jan. 5, 2013, all of which arehereby incorporated by reference in their entireties.

FIELD

The present application relates to cases for electronic devices. Morespecifically, the present application relates to a protective case thatperforms power management functions.

BACKGROUND

Many types of electronic computing devices are used for business,information, or entertainment purposes. Electronic devices includedevices such as smartphones, tablets, computers, cameras, video players,mobile communication devices, electronic media readers, audio players,handheld scanners, two-way radios, global positioning satellite (GPS)devices, and other types of electronic computing or communicationdevices, including combinations thereof. These devices often containsensitive or fragile components, such as electronic components or glassscreens, which can be easily damaged if the device is dropped, exposedto the elements, and/or exposed to substantial forces. To protect adevice from damage, an electronic device can be installed in aprotective enclosure.

Electronic devices are commonly powered by one or more internalbatteries. These batteries are often rechargeable. Typically, deviceswith more computational power, peripherals, and/or larger displaysconsume available battery power more quickly. If an electronic device'sbattery is exhausted, the device may become unusable until the batterycan be recharged or until the device can be connected to a power source.Battery capacity often becomes an issue due to factors such as: powerrequirements of the electronic device, extended usage of the electronicdevice, physical space constraints of the battery, power requirements ofperipherals attached to the electronic device, temperature extremes,unavailability of a power source for charging, decreased batterycapacity due to aging of the battery, decreased battery life due to thenumber of charge/discharge cycles a battery has endured, or combinationsthereof. These factors can reduce the usefulness of electronic devicesbecause use time of the device between recharges becomes shorter and theuser must typically recharge the device before use can continue.

In some situations, a user may carry an additional battery that has beenpreviously charged but is not electrically connected to the electronicdevice. The extra battery can be used as a replacement for a dischargedbattery. While carrying an extra battery enables the user to use thedevice again without having to find a charging source, this approach hasdrawbacks. First, the user must remember to carry the extra battery(s)because the extra battery will sometimes not be physically attached tothe electronic device. Second, replacing an exhausted battery, orswapping an exhausted battery into the electronic device for chargingpurposes, typically requires that the device be shut down, or otherwiseturned off, and restarted or rebooted. This process is ofteninconvenient and typically results in temporary loss of use of thedevice. Finally, when a charging source is available, the variousbatteries must be swapped into and out of the electronic device in orderto charge them, unless a separate host charging device is available forthe extra battery.

In some situations, some of the problems discussed above are resolvedthrough use of a supplemental battery pack that attaches to theelectronic device. The battery pack is mechanically and electricallyattached to the electronic device in a manner such that the electronicdevice can make use of both its internal battery and a supplementalbattery in the battery pack without having to shut down the electronicdevice, or otherwise temporarily remove power from the electronicdevice. However, existing solutions have drawbacks.

From an electrical standpoint, existing solutions take one of twoapproaches regarding how the two batteries (one battery in the case andone battery in the electronic device) are charged. In one approach, thetwo batteries are used and/or charged alternately. In other words, atany point in time the electronic device is only utilizing one of thebatteries or is only charging one of the batteries. When the batteriesare not being charged and one of the batteries becomes discharged, orbecomes sufficiently low in power, the electronic device and/or the caseswitches usage from one of the batteries to the other. This approach hasthe limitation that one of the batteries may be exhausted before use ofthe other begins. If the internal battery is exhausted first and theelectronic device is operating off of the supplemental battery, the userno longer has the flexibility of removing the case from the device andusing the electronic device without it.

Similarly, when charging, current is typically directed to one of thebatteries until it is fully charged. Then, the second battery is chargedusing the available charging current or using the stored power of thebattery that has just been charged. This independent charging can resultin longer charging times because the two batteries are chargedsequentially, in time. Independent charging may also require that thesupplemental battery is fully charged before charging of the internalbattery begins. A user who wishes to make sure that charging of theinternal battery begins immediately may be required to remove thecase/supplemental battery to insure that charging of the internalbattery begins immediately.

In an alternate approach, both batteries may be used and/or chargedsimultaneously as if they are a single battery. This approach presentsseveral problems. First, the user and/or the electronic device cannotselectively control which of the batteries is charged first. Second,charging batteries in parallel may not be a preferred method if thebatteries have different characteristics. Third, charging both batteriessimultaneously, without other constraints, may draw too much currentfrom the power source and/or otherwise exceed the specifications of thepower source. For example, a Universal Serial Bus (USB) interface mayonly be specified to provide 500 mA (milliamperes) of current andcharging both batteries simultaneously may exceed that limit. Drawingtoo much current from a power source may damage the power source, maydamage the device that hosts the power source (i.e., the computer inwhich a USB port is located), may cause the power source to overheat, ormay cause the power source or host device to enter a failsafe mode whichdiscontinues power until the power source or host device is reset and/orrebooted.

In some cases, electronic devices such as tablets and smartphones areused as mobile point of sale (POS) terminals. Peripheral devices, suchas a bar code scanner, are sometimes attached to the electronic deviceto perform all of the necessary POS functions. When using an electronicdevice as a mobile POS device, multiple challenges exist. First, batterypower limitations may limit how long the device can be used beforerecharging. Second, the peripherals may cause additional powermanagement challenges. Third, the electronic device may be difficult tohandle or carry while performing other functions, resulting in a risk ofdropping or breakage. Fourth, the electronic device may be difficult tohold and operate with one hand. Fifth, the peripherals may be difficultto handle, carry, and/or operate in conjunction with the electronicdevice.

SUMMARY

In one embodiment, a protective case for an electronic device having atouchscreen interface is provided. The protective case includes arechargeable battery, a first electrical connector, a second electricalconnector, and electrical circuitry. The protective case at leastpartially surrounds the electronic device when the electronic device isinstalled in the protective case. The case permits access to thetouchscreen interface of the installed electronic device. The firstelectrical connector is accessible at the outer surface of the case forelectrically connecting the protective case to an external power sourcefor receiving electrical power from the external power source. Thesecond electrical connector is accessible at the inner surface of thecase for electrically connecting the protective case to the installedelectronic device. The electrical circuitry is configured to distributea first portion of the received electrical power to the installedelectronic device through the second electrical connector and todistribute a second portion of the received electrical power to therechargeable battery of the protective case when the protective case isconnected to the external power source. The electrical circuitry is alsoconfigured to distribute stored electrical power from the rechargeablebattery of the protective case to the installed electronic devicethrough the second electrical connector when the protective case is notconnected to the external power source.

In another embodiment, a protective case for an electronic device havinga touchscreen interface includes a protective shell, a first electricalconnector, a second electrical connector, a switch, a rechargeablebattery, and a computer processor. The protective shell includes a firstcase member removably attachable to a second case member to at leastpartially enclose the electronic device when the electronic device isinstalled in the protective shell. The protective shell has an outersurface and an inner surface. The protective shell permits access to thetouchscreen interface of the installed electronic device. The firstelectrical connector is accessible at the outer surface of theprotective shell for electrically connecting the protective case to anexternal power source for receiving electrical power from the externalpower source when the external power source is electrically connected tothe protective case through the first electrical connector. The secondelectrical connector is accessible at the inner surface of theprotective shell for electrically connecting the protective case to theinstalled electronic device. The switch is accessible at the outersurface of the protective shell. The computer processor is configured todistribute a first portion of the received electrical power to theinstalled electronic device through the second electrical connector anddistribute a second portion of the received electrical power to therechargeable battery of the protective case. The computer processor isalso configured to distribute stored electrical power from therechargeable battery of the protective case to the installed electronicdevice through the second electrical connector when the protective caseis not connected to the external power source. Distribution of thestored electrical power to the installed electronic device isconditioned upon a mode of the protective case where the mode is userselectable from the switch.

In another embodiment, a protective cover for a mobile computing devicehaving a touchscreen includes a shell, a rechargeable energy storagedevice, first and second electrical connectors, a user input device, andelectrical circuitry. The shell includes a first portion removablyattachable to a second portion to at least partially surround the mobilecomputing device when the mobile computing device is installed in theshell. The shell has an outer surface and an inner surface. The shellprovides access to the touchscreen of the installed mobile computingdevice. The first electrical connector is accessible at the outersurface of the shell for temporarily electrically interconnecting theprotective cover to an external power supply for receiving electricalpower from the external power supply. The second electrical connector isattached to the inner surface of the shell for electricallyinterconnecting the protective cover to the installed mobile computingdevice. The user input device is accessible on the outer surface of theshell. When the protective cover is receiving the electrical power fromthe external power supply, the electrical circuitry is adapted fordistributing the received electrical power to the installed mobilecomputing device through the second electrical connector and to therechargeable energy storage device to charge the rechargeable energystorage device. When the protective cover is not receiving theelectrical power from the external power supply, the electricalcircuitry is adapted for distributing stored electrical power from therechargeable energy storage device of the protective cover to theinstalled mobile computing device through the second electricalconnector. Distributing the stored electrical power to the installedmobile computing device is conditioned upon a user input received at theuser input device.

Embodiments introduced herein also include other methods, apparatuses,systems with various components, and non-transitory machine-readablestorage media storing instructions that, when executed by one or moreprocessors, direct the one or more processors to perform the methods,variations of the methods, or other operations described herein. Whilemultiple embodiments are disclosed, still other embodiments will becomeapparent to those skilled in the art from the following detaileddescription, which shows and describes illustrative embodiments of theinvention. As will be realized, the invention is capable ofmodifications in various aspects, all without departing from the scopeof the present invention. Accordingly, the drawings and detaileddescription are to be regarded as illustrative in nature and notrestrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be described and explainedthrough the use of the accompanying drawings in which:

FIG. 1 shows a front perspective view of an electronic device case for amobile point of sale;

FIG. 2 shows an exploded front perspective view of an electronic devicecase for a mobile point of sale;

FIG. 3 shows an exploded front perspective view of an electronic devicecase for a mobile point of sale along with a tablet computer and dockingstation;

FIG. 4 shows an exploded rear perspective view of an electronic devicecase for a mobile point of sale along with a tablet computer;

FIG. 5 shows an exploded rear perspective view of an electronic devicecase for a mobile point of sale along with a tablet computer and dockingstation;

FIG. 6 shows a rear perspective view of an electronic device case for amobile point of sale;

FIG. 7 shows a rear perspective view of an electronic device case for amobile point of sale positioned in a docking station;

FIG. 8 shows a front perspective view of an electronic device case for amobile point of sale positioned in a docking station;

FIG. 9 illustrates a case for an electronic device with components formanaging power in one embodiment of the techniques disclosed herein;

FIG. 10 illustrates a case interfaced to a power source and a device inone embodiment of the techniques disclosed herein;

FIG. 11 illustrates a method of distributing current between a case andan electronic device in one embodiment of the techniques disclosedherein;

FIG. 12 illustrates an alternate method of distributing current betweena case and an electronic device in another embodiment of the techniquesdisclosed herein;

FIG. 13 illustrates a computer system for performing the techniquesdisclosed herein;

FIG. 14 shows a rear perspective view of a credit card being swipedthrough a card runway of the case;

FIG. 15 shows a rear perspective view of an electronic device case witha shoulder strap and rotatable mount without a hand strap;

FIG. 16 shows an electronic device case in a single-bay docking stationand a plurality of electronic device cases in a multi-bay dockingstation;

FIG. 17 shows a rear view and projected views of an electronic devicecase for a mobile point of sale;

FIG. 18 shows a rear perspective view of an electronic device case for amobile point of sale; and

FIG. 19 shows a rear and front perspective view of an electronic devicecase for a mobile point of sale.

DETAILED DESCRIPTION

In the following detailed description, various specific details are setforth in order to provide an understanding of and describe theapparatuses and techniques introduced here. However, the techniques maybe practiced without the specific details set forth in these examples.Various alternatives, modifications, and/or equivalents will be apparentto those skilled in the art without varying from the spirit of theintroduced apparatuses and techniques. For example, while theembodiments described herein refer to particular features, the scope ofthis solution also includes embodiments having different combinations offeatures and embodiments that do not include all of the describedfeatures. Accordingly, the scope of the techniques and solutionsintroduced herein are intended to embrace all such alternatives,modifications, and variations as fall within the scope of the claims,together with all equivalents thereof. Therefore, the description shouldnot be taken as limiting the scope of the invention, which is defined bythe claims.

The terms “case” and “protective enclosure” are used interchangeablyherein and are intended to have the same meaning throughout thisspecification. A protective enclosure 100 can surround and protect anelectronic device. The protective enclosure can include a front shell210 and a back shell 215 as shown in FIG. 2. The front shell 210 cancover at least a portion of a front surface of the electronic device205, and the back shell 215 can cover at least a portion of a backsurface of the electronic device. The protective enclosure can be madefrom any suitable material, such as polycarbonate, fiberglass fillednylon, aluminum, stainless steel, or carbon fiber.

The front shell 210 can attach to the back shell 215 in any suitableway. For example, the front shell 210 can attach to the back shell 215with fasteners, adhesive, or retention features. Retention features caninclude a plurality of tabs 505 extending from front shell 210, as shownin FIG. 5. The plurality of tabs can be configured to mate with aplurality of slots 250 in the back shell 215, as shown in FIG. 2.Alternately, a plurality of tabs in the back shell 215 can be configuredto mate with a plurality of slots in the front shell 210.

The protective enclosure 100 can be made using any suitablemanufacturing process, such as injection molding. In one example, theprotective enclosure 100 can include overmolded portions to protect theelectronic device from drops, provide improved feel and grip for a user,or provide additional friction to prevent the enclosure from sliding onsmooth surfaces, such as store counters. In an overmolding process, suchas insert molding or multi-shot molding, a first material can be moldedonto a second material. In one example, the first material can be athermoplastic elastomer (TPE) and the second material can be a rigidplastic, such as polycarbonate. As a result of the overmolding process,the overmolded first material can form a strong bond with the secondmaterial. The use of primers or adhesives in the overmolding process maynot be required to achieve a suitable bond between the first and secondmaterials.

The protective enclosure 100 can include data input devices to allow theelectronic device to serve as a mobile point of sale. The data inputdevices can allow the electronic device 405 to perform a variety ofmobile transactions or tasks, such as retail transactions orinventory-related tasks. The data input devices can include a paymentdevice reader and a product information input device. In one example,the product information input device can be a bar code reader 230, asshown in FIGS. 4 and 6. The bar code reader 230 can be attached to theprotective enclosure 100 in any suitable way or can be detachable fromthe protective enclosure 100. In one example, the bar code reader 230can be mounted to the back shell 215 in a bar code reader bay 245 asshown in FIG. 2. The bar code reader 230 can be attached to the backshell 215 using fasteners or can snap into the bar code reader bay 245using retention features to simplify assembly.

In one example, the payment device reader can be a magnetic card reader225, as shown in FIG. 2. The magnetic card reader 225 can be mounted tothe protective enclosure 100 in any suitable way. In one example, asshown in FIGS. 2, 6 and 14, the magnetic card reader 225 can be mountedto a card runway 410 that is mounted on an outer surface of theprotective enclosure 100. The card runway 410 can be mounted flush witha back surface of the back shell 215 of the protective enclosure 100.

The protective enclosure 100 can include a flexible insert 205 thatsurrounds at least a portion of the electronic device 405 and protectsthe electronic device. The flexible insert 205 can be positioned betweenthe electronic device 405 and the front and back shells (210, 215). Theflexible insert 205 can provide cushioning to the electronic device 405during regular use or in the event of an accident. For example, theflexible insert 205 can absorb shocks resulting from dropping theelectronic device 405 onto a hard surface. The flexible insert 205 canbe made from any suitable material, such as, for example, foam material,silicone rubber, fabric, or thermoplastic elastomer. Any suitable typeof foam can be used for the flexible insert 205, including open-cellpolyurethane or closed-cell polyethylene. Likewise, any suitable type offabric can be used for the flexible insert 205, including synthetic,natural, or semi-synthetic fabrics.

The flexible insert 205 can be configured to cover at least a backportion and at least a front portion of the electronic device 405. Theflexible insert 205 can be configured to wrap around the edges of theelectronic device 405 to prevent the device from directly contacting thefront or back shells (210, 215) of the protective enclosure 100. Such aconfiguration can prevent impact forces from being transferred directlyfrom the front or back shells (210, 215) to the electronic device 405.Also, preventing the electronic device 405 from directly contacting thefront or back shells (210, 215) can prevent the inner surfaces of theshells from scratching the outer surfaces of the electronic device 405.

The flexible insert 205 can have any suitable thickness to provideadequate protection to the electronic device 405. In one example, theelectronic device 405 can be a tablet computer, such as an APPLE IPAD,and the flexible insert 205 can be a foam material with a thickness ofabout 0.125 to 0.75, 0.125 to 0.5, 0.125 to 0.375, or 0.125 to 0.25.

The flexible insert 205 can include openings to accommodate variousconnectors, components, and fasteners within the protective enclosure100, as shown in FIG. 4. The flexible insert 205 can include a batteryopening 440 to accommodate a battery 220 positioned between an innersurface of the back shell 215 and the electronic device 405. In anotherexample, the flexible insert 205 can include a bar code reader opening445 to accommodate a bar code reader 230 between the back shell 215 andthe electronic device 405. These openings (e.g. 440, 445) can provideclearance volumes between the back shell 215 and the protective case 405to house various components. In addition, the perimeter of each opening(e.g. 440, 445) can provide cushioning to a component positioned in theopening. For example, the perimeter of the bar code reader opening 445can provide cushioning to the bar code reader 230, thereby protectingthe bar code reader 230 during a drop and potentially extending itsuseful life.

Materials with high impact absorption properties, such as fabric, rubberor foam materials, often have low thermal conductivities. Under certaincircumstances, encapsulating an electronic device 405 in a materialhaving a low thermal conductivity can result in overheating of theelectronic device or decreased battery performance. To avoid theseissues, the flexible insert 205 can be made of, at least partially, amaterial having a high thermal conductivity to prevent the electronicdevice 405 or components (e.g. 220, 230) within the protective enclosurefrom overheating. For instance, the flexible insert 205 can be made froma material having a thermal conductivity greater than 0.5, 1, 10, 25,50, or 100 W/(m-K) at standard temperature. In one example, the entireflexible insert 205 can be made from a material having a high thermalconductivity. In another example, at least a portion of the flexibleinsert 205 can be made from a material having a high thermalconductivity. Thermally conductive portions of the flexible insert 205can be thermally connected to a heat dissipation device, such as a finstructure, located on an outer surface of the protective enclosure. Inanother example, the thermally conductive portions of the flexibleinsert 205 can be thermally connected to the inner surface of the backshell that can be made from a material with a high thermal conductivity,such as aluminum. In this example, convective or conductive cooling canprovide heat dissipation from the outer surface of the protectiveenclosure.

The protective enclosure 100 can include a heat dissipation device thatis not part of the flexible insert 205. For example, the protectiveenclosure 100 can include one or more heat sinks placed in physicalcontact with an outer surface of the electronic device 405, the battery220, or any of the electrical components (e.g. 230) housed in theprotective enclosure. In one example, the heat sinks can be thermallyconnected to heat dissipation devices, which can include fin structureslocated on an outer surface of the protective enclosure 100. The heatsinks can be made from any material having a suitable thermalconductivity, such as a material having a thermal conductivity greaterthan 0.5, 1, 10, 25, 50, or 100 W/(m-K) at standard temperature. Theheat sinks can transfer heat from the electronic device 405 orcomponents of the protective enclosure 100 and transfer that heat to theheat dissipation devices where it can be transferred to the surroundingatmosphere.

To prevent the heat dissipation device from also transferring impactforces from the outer surface of the protective enclosure to theelectronic device 405 or components (e.g. 220, 230) in the event of adrop, it can be desirable to make thermal pathways that are non-rigid. Athermal pathway can connect a heat sink that is in physical contact withthe electronic device to a fin structure located on a back surface ofthe back shell 215. In one example, the thermal pathway can be made froma thermally conductive tape that has a suitable cross-sectional area toprovide adequate heat transfer rates while also having sufficientflexibility to avoid transferring impact forces to the electronicdevice. The thermally conductive tape can have a cross-sectional area ofgreater than 1.0, 2, 10, or 20 mm².

The protective enclosure can include air channels (not shown) to providecooling for the electronic device 405. In one example, air channels canbe formed in the flexible insert 205 to allow for dissipation of heatfrom the electronic device 405 or other components within the protectiveenclosure. The air channels can extend from an outer surface of theelectronic device 405 to an outer surface of the back shell 215 or thefront shell 210. In one example, the back shell can include one or moreopenings to permit airflow to and from the electronic device 405 throughthe air channels. The one or more openings can include covers, such asmesh covers to prevent debris from entering the air channels.

In one example, the protective enclosure can include a fan (not shown)to provide forced convection through the air channels to increase therate of heat dissipation. The fan can be mounted within the protectiveenclosure 100 and can be controllable. For instance, the fan can beturned on when the temperature within the protective enclosure 100 orthe temperature of the electronic device 405 reaches a predeterminedtemperature. The protective enclosure can 100 include a temperaturemeasurement device or can rely on a built-in temperature measurementdevice in the electronic device 405 to determine temperature. When atemperature exceeds the predetermined temperature, the fan can be turnedon. Since the fan will consume power from the battery, it may only bedesirable to turn on the fan under certain circumstances. For example,the fan may turn on when the power conserved by reducing the operatingtemperature of the electronic device 405 or the battery 220 will exceedthe amount of power consumed by the fan. In one example, the user can beprompted with a warning regarding high operating temperature and canchoose to activate the fan, increase the predetermined temperature, orturn off the electronic device and permit it to cool without operatingthe fan.

The protective enclosure 100 can include a hand strap 415, as shown inFIG. 6. The hand strap 415 can allow the user to hold and maneuver theprotective enclosure 100 with one hand. Since the user can hold theprotective enclosure 100 with one hand, the user has free use of theirsecond hand to accomplish other tasks simultaneously, such as operatingthe touch screen 335 of the electronic device 405, swiping a credit card1405 through the card runway 410 (shown in FIG. 14), or operating thebar code reader 230. The hand strap 415 can be attached to a rotatablemount 610 that allows the hand strap 415 to rotate relative to theprotective enclosure 100.

The rotatable mount 610 can attach to the protective enclosure 100 inany suitable way. In one example, the rotatable mount 610 can include afirst mount portion 425 and a second mount portion 420, as shown in FIG.6. The first mount portion 425 can have a circular perimeter and canmount to the back shell 215 of the protective enclosure 100. The secondmount portion 420 can be rotatably captured between the first mountportion 425 and the back shell 215. The first mount portion 425 caninclude a plurality of teeth 440 that extend into a plurality of slots435 in the back shell 215, as shown in FIG. 2. Once the plurality ofteeth 440 have been inserted into the plurality of slots 435, a partialrotation (in a first direction) of the first mount portion 425 can lockthe plurality of teeth 440 into a plurality of retention features 445 onan inner surface 450 of the back shell 215. The plurality of retentionfeatures 445 can be integrated into the plurality of slots 435, as shownin FIG. 2. For instance, the plurality of retention features 445 caneach include a sloped surface that engages with a tooth and results inincreasing friction between the tooth 440 and the retention feature asthe angle of rotation of the first mount portion 420 is increased duringinstallation. At a certain angle of rotation, the friction between theteeth and the retention features is sufficient to lock the first mountportion 425 to the back shell 215. To prevent decoupling of the teethfrom the retention features, a fastener can be used to prevent rotationof the first mount portion 425 relative to the back shell 215.

Rotation of the first mount portion 425 in a second direction oppositethe first direction can release the plurality of teeth 440 form theplurality of retention features 445 and allow the first mount portion420, and the entire rotatable mount 610, to be removed from theprotective enclosure 100. By removing the rotatable mount 610, the backsurface of the protective enclosure 100 can become substantially flat.This can allow the protective enclosure to rest flush against a surface,such as a store counter, which may be preferable for some users.Removing the rotatable mount 610 can expose the plurality of slots 435in the back shell 215. To improve aesthetics of the protective enclosure100, and to prevent liquid or debris from entering the protectiveenclosure through the plurality of slots 435, the slots can be sealedwith a suitable slot cover. In one example, the slot cover can bepositioned on an inner surface of the back shell 215 and can includeprotrusions that extend into the plurality of slots 435 and are flushwith a back surface of the protective enclosure 100.

Any suitable method can be used to attach the rotatable mount 610 to theprotective enclosure 100. For instance, fasteners, such as screws,VELCRO, or snaps can be used to secure the rotatable mount 610 to theback shell 215. These fasteners can be used in addition to the pluralityof teeth and the retention features described above or can be alternatemethod of attaching the rotatable mount 610 to the protective enclosure100.

The second mount portion 420 can be rotatably captured between the firstmount portion 425 and the back shell 215. Consequently, the second mountportion 420 can rotate independently of the first mount portion 425 andthe back shell 215. As shown in FIGS. 18 and 19, the second mountportion 420 can rotate across a range of angular positions. The secondmount portion 420 can include a first opening 615 and a second opening620 that are configured to receive the hand strap 415. The hand strap415 can attach to the first and second openings (615, 620) by anysuitable method. In one example, the hand strap 415 can be fed throughthe first opening 615 and the second opening 620 and can be looped backand secured to itself by stitching or adhesive. A hand slot can beformed between the hand strap 415 and the first mount portion 425, andthe hand slot can be any suitable size to receive a user's hand with theuser's palm resting against the first mount portion 425. In one example,the hand strap 415 can be adjustable to alter the size of the hand slotto accommodate various hand sizes. In another example, the hand strap415 can be made of elastic to create a one-size-fits-all hand slot.

To allow the user to easily remove the rotatable mount 610 withoutspecial tools, the first mount portion 425 can include a ring gearextending partially or fully around an outer cylindrical surface of thefirst mount portion. In addition, the second mount portion 420 caninclude an internal ring gear extending partially or fully around aninner cylindrical surface of the thru hole in the second mount portion,where the thru hole is configured to receive the first mount portion 425when the first and second mount portions (425, 420) are assembled to thecase 100. When the first and second mount portions (425, 420) areassembled to the back shell 215 of the case 100, there may be a radialclearance distance between the internal ring gear and the external ringgear. The radial clearance distance between the internal ring gear andthe external ring gear can allow the second mount portion 420 to rotatefreely when the first and second mount portions (425, 420) are assembledto the back shell 215. The radial clearance distance between theinternal ring gear and the external ring gear can have any suitablevalue, and should account for manufacturing tolerances, assemblytolerances, and a desire for the second mount portion 425 to rotatefreely from the first mount portion 420 during normal use. In certainexamples, the radial clearance distance between the internal ring gearand the external ring gear can be about 0.005-0.100, 0.005-0.05,0.010-0.05, or 0.010-0.020. As shown in FIG. 6, the second mount portion420 can include a first upright portion that includes the first opening615 and a second upright portion that includes the second opening 620.By applying a clamping force to the first and second uprights of thesecond mount portion 420, such as by squeezing the first and secondupright portions between a thumb and forefinger, where the thumb pressesagainst an outer wall of the first upright and the forefinger pressesagainst an outer wall of the second upright, the user can deflect thefirst and second uprights of the second mounting portion 420 inwardtoward each other. As a result, the thru hole in the second mountportion 420 will become eccentric as the diameter of the thru holebetween the first and second uprights decreases, and the internal ringgear on the second mounting portion will be urged inward to a pointwhere the internal ring gear engages with the external ring gear on thefirst mount portion 425. The user can then rotate the second mountportion 425, which will cause the first mount portion 420 to rotate dueto engagement between the internal ring gear and the external ring gear.This rotation of the first mount portion 425 will release the pluralityof teeth 440 from the plurality of retention features 445, and allow thefirst mount portion 420, and the entire rotatable mount 610, to beremoved from the protective enclosure 100. This feature allows the userto easily remove the rotatable mount without need for special tools.This can be especially useful in commercial settings where the user maynot have access to special tools or may not be comfortable using specialtools.

The internal ring gear on the second mount portion 425 can include anysuitable feature or features that allow it to transmit torque to theexternal ring gear on the first mount portion 420. In one example, theinternal ring gear can include one or more teeth that are configured toengage one or more teeth on the external ring gear to transmit torqueapplied by the user to the second mount portion 425. The teeth on theinternal and external ring gears can have any suitable shape, includingtriangular, square, curved, or any combination thereof.

The protective enclosure 100 can include a shoulder strap to reducefatigue of a user's arm caused by weight of the mobile point of sale.The shoulder strap can attach to the protective enclosure 100 using anysuitable form of attachment. For example, the shoulder strap 1510 canattach to the protective enclosure 100 using fasteners 1505, as shown inFIG. 15. The fasteners 1505 can be buttons or snaps that allow for easyattachment and removal. The fasteners 1505 can attach to the enclosureat various attachment points. The attachment points can allow thefasteners 1505 to swivel with respect to the protective enclosure 100.In one example, the attachment points 1515 can be located near themiddle of the side surface of the protective enclosure, as shown in FIG.15. This configuration can allow the user to easily rotate the displayscreen of the electronic device toward or away from their body dependingon desired usage. In another example shown in FIG. 19, the attachmentpoints 1915 can be located near the ends of the side surface of theprotective enclosure to allow for additional usage options.

The protective enclosure 100 can include a trigger 605 that can beconfigured to activate various features of the protective enclosure. Inone example, the trigger 605 can be a trigger with an arcuate shape, asshown in FIG. 6. The trigger can be configured to activate any of thedata input devices. For instance, depressing the trigger 605 canactivate the bar code reader 230 or the credit card reader 225, as shownin FIG. 3. Having an arcuate trigger 605 can allow all portions of thetrigger 605 to be equidistant from the point of rotation of therotatable mount 610, which can allow the user to easily activate thetrigger 605 across a range of angular positions of the rotatable mount.For example, the user may switch between a landscape mode and a portraitmode within the electronic device 405 simply by rotating the rotatablemount 610. Even as the user's hand position changes relative to the backshell 215 of the protective enclosure 100, at least one of the user'sfingers can remain near the trigger 605 to permit actuation of thetrigger. Likewise, if the protective enclosure 100 is swapped between auser's right hand and left hand, at least one of the user's fingers canremain near the trigger 605 to permit actuation of the trigger.

The protective enclosure 100 can include a trigger member 430, as shownin FIG. 3. The trigger member 430 can include a base portion 310 thatcan be firmly secured to an inner surface of the back shell 215 using,for example, fasteners. The trigger member 430 can include a pluralityof fingers 305 extending from the base portion 310 and connecting to anarcuate portion 320 of the trigger member 430. The arcuate portion 320of the trigger member 430 can be located proximate an inner surface 315of the trigger 605. The inner surface 315 of the trigger 605 can beopposite the outer surface of the trigger where the user's fingerscontact the trigger 605. Depressing the trigger 605 inwardly toward theelectronic device 405 can cause the arcuate portion 320 of the triggermember 430 to deflect relative to the back shell 215 of the protectiveenclosure. As a result, the arcuate portion 320 of the trigger member430 may deflect a suitable distance to actuate a button (not shown)mounted within the protective enclosure. Actuation of the button can beconfigured to cause a feature of the protective enclosure to becomeactive, such as the bar code reader 230. In one example, the actionelicited by actuation of the button can be user-selectable.

The protective enclosure 100 can include more than one button positionednear the trigger member 430. For example, buttons can be mounted onbutton mounts 330 on an inner surface of the protective enclosure.Depressing the trigger 605 at certain positions along its length canresult in actuation of certain buttons. For example, depressing a firstportion 1805 of the trigger, such as a left portion, can actuate a firstbutton and depressing a second portion 1810 of the trigger, such as aright portion, can actuate a second button, as shown in FIG. 18. Thefirst button can be used to scroll through a menu, and the second buttoncan be used to select an option from the menu. For example, the firstbutton can be used to scroll through a menu of payment options (e.g.debit or credit), and the second button can be used to select a paymentoption. This can allow the user to hold and operate the electronicdevice with a single hand, which frees their second hand for othertasks. Where the electronic device is a touch screen device, thisfeature can allow a gloved user to operate the electronic device 405without removing their gloves. This can improve efficiency and safety.In a first example, a rental car employee working in a cold environmentcan check-in returning vehicles without removing their gloves, therebyincreasing efficiency. In a second example, a hospital employee workingin a sterile environment can take inventory of medical supplies withoutremoving surgical gloves, thereby improving safety.

Where the protective enclosure 100 includes multiple buttons, thetrigger member 430 can include several discrete portions instead of onecontinuous portion along the length of the trigger 605. Each discreteportion of the trigger member 430 can enhance performance of the triggerby ensuring that when one button is actuated, adjacent buttons are notactuated accidentally by unintended deflection of the trigger member.

The protective enclosure can include a flexible membrane 1920 to allowfor operability of a touch screen 335 on the electronic device 405, asshown in FIGS. 1 and 19. For example, the front shell 210 can include adisplay opening 235 that is covered by the flexible membrane 1920. Inone example, the flexible membrane 1920 can be made from a thin layer ofpolycarbonate (e.g. LEXAN), polyvinyl chloride (PVC), polyurethane, orsilicone that can be molded, such as by thermoforming, casting,stretching, heating, or injection molding, or otherwise shaped to fitover the front surface of the electronic device 405 or other surfaces ofthe electronic device. The flexible membrane 1920 can have a thicknessranging from about 0.004 to 0.020 inches. The flexible membrane 1920 canbe made from a single material or multiple materials that are welded,glued, or formed together into a single membrane. For a portion of theflexible membrane 1920 that is disposed over the touch screen 335 of theelectronic device 405, it can be desirable to use a clear, thin layer ofglass or plastic to provide a clear, transparent material over thescreen to protect the screen from scratches while also permittingoperability of the touch screen. If the electronic device 405 includes akeyboard, a portion of the flexible membrane that covers the keyboardcan be made of a thin layer of polycarbonate (e.g. LEXAN), PVC,polyurethane, or silicone that is flexible so that the keyboard or otherbuttons can be pressed through the membrane, which can provide a similarfeel as using the keyboard without the flexible membrane.

The protective enclosure can include a charge indicator 115. The chargeindicator 115 can be located proximate an outer surface of theprotective enclosure. As shown in FIG. 1, the charge indicator 115 canbe a series of LEDs, and each LED can represent a percentage of chargeremaining when illuminated. For example, if the charge remaining in thebattery is less than 75 percent but greater than 50 percent, two out offour LEDs may be illuminated. The charge indicator 115 can display thecharge remaining in the electronic device 405, battery 220, or both andcan be selectable by the user.

The protective enclosure can include various openings to allow foroperability of the electronic device 405 by the user. For example, theprotective enclosure 100 can include an opening for a camera, cameraflash, switch, volume control button, headphone jack, power button, ormicrophone of the electronic device 405. The microphone opening can beconfigured to avoid introducing echoes or reverberations into the soundwaves that are received by the microphone of the electronic device 405.In another example, the protective enclosure 100 can include a speakeropening 110 to accommodate a speaker of the electronic device. Thespeaker opening 110 can redirect sound waves generated by the speakerlocated on a back or end surface of the electronic device upwardly atthe user, thereby improving the directivity of the sound waves andmaking sound appear louder to the user. This can be desirable low-powerspeakers that are often included in mobile electronic devices.

FIG. 9 illustrates case 930 for an electronic device with components formanaging power in one embodiment of the techniques disclosed herein.Case 930 includes current control module 929, battery charger 922, casebattery 923, battery monitor 924, data input device(s) 933, andprocessor 921. Back shell 215 is an example of case 930, although otherconfigurations are possible. The illustrated elements of case 930 may beassembled on one or more circuit boards. Case 930 may also includemechanical components and functions as illustrated in FIGS. 1-8 and theaccompanying explanations.

Processor 921 may be any type of microcontroller, microprocessor,microcomputer, programmable logic device, reconfigurable circuit, orapplication specific circuit that is configured to communicate withother elements of case 930 to perform the described power managementfunctions. In some situations, these power management functions may bedescribed as ‘intelligent’ power management functions.

In some configurations, processor 921 may also communicate with anelectronic device to which case 930 is attached, communicate with apower source, communicate with other devices, or with combinationsthereof. Electronic device 405 is one example of an electronic devicewith which processor 921 communicates. Processor 921 may make use ofcomputer executable program instructions that are stored in processor921. Alternately, the computer executable program instructions may bestored in a memory device that is separate from processor 921.

Battery 923 is a rechargeable battery for supplying power to a device towhich case 930 is attached. Battery 923 may use one or more of a varietyof battery technologies including lithium ion (Li-ion), lithium ionpolymer (Li-ion polymer), lead-acid, nickel cadmium (NiCd), nickel metalhydride (NiMH), nickel-zinc, alkaline, or others. Battery 923 storeschemical energy which can be converted into electrical energy and can beprovided to an electronic device, such as electronic device 405, towhich case 930 is attached. Battery 220 is one example of battery 923.

Although additional batteries are possible, for purposes of simplifyingthe discussion herein, the examples provided are generally limited toexamples of cases with a single battery and electronic devices with asingle battery. However, the solutions and techniques disclosed hereinmay be implemented in a fundamentally similar manner when the caseand/or the electronic device have two or more batteries.

Battery charger 922 is a device, or collection of devices, for chargingbattery 923 using current received from current control module 929.Battery charger 922 may charge battery 923 by transitioning throughmultiple charging phases such as conditioning, constant current, andconstant voltage. The state of battery charger 922, chargingcharacteristics, or a charge mode may be commanded or controlled byprocessor 921. Processor 921 may also monitor the status of charging orcharge activities through communication with battery charger 922.Battery charger 922 may be capable of charging battery 923 usingdifferent charging algorithms (i.e., fast charge, slow charge, etc.).Battery charger 922 may also perform thermal management functions withrespect to the charging activities.

Battery monitor 924 is a device or group of devices for monitoring acondition of one or more batteries such as battery 923. Battery monitor924 may be a microcontroller peripheral that provides batterycharge/fuel gauging functions. Battery monitor 924 may use one or moreknown algorithms for fuel gauging and may provide information related tovarious statistics such as remaining battery capacity, state-of-charge(i.e., percentage remaining), run-time to empty, battery voltage, and/orbattery temperature. Battery monitor 924 may be configured for orcommanded to provide some or all of these types of information toprocessor 921. In addition, battery monitor 924 may be capable of beingconfigured for or commanded to these different modes by processor 921.

Current control module 929 is a device that can be configured for orcommanded to limit or restrict the amount of current that is drawn fromor flows from a power source attached to case 930. Current controlmodule 929 may also be configured to control or limit the amount ofcurrent that flows from individual outputs of current control module929, such as to an electronic device and to battery charger 922. Currentcontrol module 929 may be pre-programmed to perform these functions ormay be configured for or commanded to perform these functions byprocessor 921. Current control module 929 may also include capabilitiesto measure or monitor the amount of current being used by variousattached devices such as battery charger 922 and/or an attachedelectronic device. Current control module 929 may also limit surges ofcurrent when power is applied to or removed from case 930.

In one example of operation, processor 921 determines an amount ofsource current available from a power source providing power to case930. While some power sources may be capable of supplying more powerthan they are specified to provide, drawing current from a power sourcebeyond its specified capabilities may damage the power source or damagethe device that is hosting the power source (i.e., a computer hosting aUSB port from which power is being drawn). Determining how much currentis available from a power source may be accomplished using one or moreof several methods including: determining a type of the power sourcebased on the type of connector used, determining a type of the powersource based on information received about the power source, determininga type of the power source based on other characteristics of the powersource, or determining the maximum capability of the power sourcethrough trial and error testing. Each of these four methods is discussedin detail below.

A first method for determining how much current is available from apower source is to use a default value based on the type of connectorthat is used to connect to the power source. For example, if the poweris supplied to case 930 through a USB connector, processor 921 may use adefault current limit of 500 mA for the current source. The power sourcemay be treated as only being able to provide this amount of current,based on the connector type, even though the power source may actuallybe capable of providing higher levels of current.

A second method of determining how much current is available from apower source is to determine a type of the power source based oninformation or data received about the power source. For instance,processor 921 may receive information, through communication with thepower source or another device, indicating that the power source iscapable of supplying up to a specified maximum amount of current.Processor 921 then uses this information to direct current controlmodule 929 to limit the total current drawn from the current source. Thetotal current includes current used by battery charger 922, current usedto operate other components of case 930, and current directed to anelectronic device attached to case 930.

A third method of determining how much current is available from thepower source is to determine a type of the power source based on acharacteristic of the power source or information provided by the powersource. The power source may communicate information about its identityor characteristics to case 930 or another host device. In the case of apower source connected using a USB connector, the data lines associatedwith the connector may not be otherwise used for delivering power andmay be used to indicate capabilities of the power source. For example,APPLE chargers typically indicate the available current from the chargerby applying specific voltages on the D+ and D− USB lines. When D+ and D−are both held at 2.0V, a device may use up to 500 mA of current from thepower source. When D+ is held at 2.0V and D− is held at 2.8 V, a devicemay use up to 1 A of current from the charger. By detecting voltages onthese lines, or data pins, case 930 can determine a maximum amount ofcurrent to draw from the power source. In some situations, the voltagesor states of D+ and D− may be propagated through case 930 and/orduplicated at a connector to an attached electronic device. This enablesthe electronic device to detect what type of power source is being usedeven though the electronic device is not directly connected to the powersource. Many other configurations and methods of detectingcharacteristics of or information about the power source are possible.

A power source may use D+ and D− to indicate capabilities of the powersource, as described above, in a temporary or permanent manner. Forexample, the power source may indicate the capabilities, and/or othercharacteristics, of the power source by asserting predetermined voltageson the D+ and/or D− lines, as described above, throughout the entireperiod of time the power source is connected to a device. Alternately,the power source may assert these voltages on the D+ and D− lines foronly a shortened period of time. In one example, the power sourceasserts the capability indicating voltages for a predetermined number ofseconds when a device is initially connected and then reverts to usingthe D+ and/or the D− line for other purposes, such as transferring data.

A fourth method of determining a maximum current limit or other powercapabilities of a power source is conducting of trial and error testing.A host device using power from a power source may iteratively drawincreasing levels of power or current from the power source until thereis an indication that the power source is reaching or has reached itsmaximum capabilities. In one case, the indication that the power sourceis nearing its maximum capability may be indicated by the power sourcehaving difficulty maintaining a supply voltage. For example, if a powersource is supplying power at 5V and is having difficulty meetingincreasing current requirements, the supply voltage may begin droppingto 4.9V, 4.8V, or lower. By gradually increasing the current draw fromthe power source and detecting changes in the supply voltage, or someother characteristic of the supplied power, the host can the determine amaximum current draw for the power source.

In another configuration, a maximum capability of a power source may beindicated when the power source reaches a failsafe or circuit breakermode. For example, some power sources are designed with protectioncapabilities that limit or discontinue output from the power source if amaximum power, voltage, or current draw is exceeded. A device usingpower from the source can experimentally determine this maximum power orcurrent capability by gradually increasing current or power draw fromthe power source until a failsafe of circuit breaker limit of this typeis reached and then set a maximum power or current draw value for thepower source at an amount that is less than the identified failsafe orcircuit breaker limit. In some situations, the power source may have tobe reset, rebooted, or be otherwise reconfigured after it has reached afailsafe or circuit breaker limit.

Processor 921 may also configure or command current control module 929to limit an amount of current that is delivered to each of severaloutputs of current control module 929. For example, in FIG. 9, currentcontrol module 929 has one output to battery charger 922 for chargingbattery 923 and one output which supplies power directly to anelectronic device, such as electronic device 220. Case 930 may beconfigured to manage how power or current is distributed among one ormore internal batteries and an electronic device attached to the case ina number of different ways, as will be described in detail below.

In one configuration, an electronic device connected to case 930 ispermitted to consume as much of the available current from the powersource as it can consume, up to a maximum current limit which has beendetermined by processor 921 and is being controlled by current controlmodule 929. If the electronic device is consuming less current than themaximum current limit, processor 921 then commands current controlmodule 929 to permit the balance of the available current (i.e., thecurrent limit minus the current being used by the electronic device) tobe sent to battery charger 922 for charging battery 923. In this way,the electronic device is permitted to use the maximum amount of currentit can consume for charging its internal battery while using anyremaining available current for charging battery 923 in case 930 andwithout exceeding the maximum current available from the source. Indetermining the balance of the available current, the current consumedby other components of case 930 may also be taken into account.

In the configuration described above, the current drawn from the powersource is limited to the maximum value designated for that power source,but the current path from the power source to the electronic device isnot limited to any specific amount below that maximum value. Presumingthe current consumption of the electronic device does not exceed themaximum limit for the power source, the electronic device uses, in thisconfiguration, essentially the same amount of current and charges atessentially the same rate as it would if it were connected directly tothe power source. This allows the electronic device to be charged at themaximum rate which is safe for the power source while making use of anyadditional current which is not being used by the electronic device tocharge battery 923.

In another configuration, the current supplied to the electronic devicefrom a power source is limited by case 930 to a maximum value that isless than a maximum current that can be drawn from the power source. Forexample, a power source connected to case 930 may be specified forsupplying 2A of current. However, case 930 may limit the amount ofcurrent supplied to the electronic device to a lower value. Thislimitation may be imposed in order to reserve current for charging ofbattery 923, or for other reasons such as for thermal control. This typeof control over current allocation allows case 930 to control the rateat which the electronic device is charged, while reserving a designatedportion of the current to charging battery 923. In this way, battery 923and a battery in the electronic device can be simultaneously charged ina controlled manner. Also, the rate of charge of each of these twobatteries and/or the relative priority of their charging can becontrolled by controlling how much current is allocated to each. Whilethe current delivered to the electronic device is primarily described ascurrent for charging the battery of the electronic device, it should beunderstood that current delivered to the electronic device may also beused to operate the electronic device depending on the state of theelectronic device and the state of the battery of the electronic device.

In some situations, current control module 929 may not limit the currentthat flows from the power source directly to an electronic deviceattached to case 930, but may simply act as a current measuring devicewhich provides an indication of how much current the electronic deviceis using. Similar to previous examples, this information may be used todetermine how much additional current is available for and should beallocated to battery charger 922 for purposes of charging battery 923.

In some configurations, case 930 may have two or more power connectorsfor connecting to various types of power sources. In the example of twopower connectors, one may be configured for connection to a low powersource with limited power capability (i.e., a low power source) whilethe other may be configured for connection to a power source withincrease power capabilities (i.e., a high power source). A singlecurrent control module, such as current control module 939 may beconfigured to operate with both power sources or separate currentcontrol modules may be associated with each of the two power inputs. Thedifferent power source connections may have different mechanicalcharacteristics. In one example, the low power connector may be a miniUSB connector, such as port 1705, while the high power connector may bea connector such as connector 105, as shown in FIG. 1. In some cases oneof the connectors may comprise contact surfaces rather than a connectorwith an engagement mechanism. Contact surfaces often provide moreconductor area for conducting larger amounts of power. In addition,contact surfaces may allow case 930 to be more easily be placed inelectrical contact with a power source because the use of these types ofelectrical contacts will typically relax the alignment requirements formaking a connection. In one example, the high power connector may beengaged by simply lowering case 930 into a docking device such as adocking station 505. In this example, the electrical connection may bemaintained by the weight of case 930 and the associated electronicdevice.

While many of the functions of case 930 are described as beingcontrolled by processor 921, it should be understood that amicroprocessor is not required to perform the techniques described here.The techniques may also be performed by a logic state machine and/orelectrical circuitry configured for these purposes.

In other configurations, case 930 may charge from a power sourcewirelessly. Wireless or inductive charging relies on an electromagneticfield to transfer power between a power source and case 930. The powersource will typically have an induction coil to create an alternatingelectromagnetic field. Case 930 will also have an induction coil that,when placed closely enough the induction coil of the power source,captures power from the electromagnetic field and converts it back intoelectrical current for case 930.

In FIG. 9, the determination regarding how the available current will beallocated among the electronic device and battery charger 922 (forcharging battery 923) may be based on a variety of factors. Thesefactors may include: the charge state of battery 923, the charge stateof the battery of the electronic device, the capacity of battery 923,the capacity of the battery of the electronic device, charging rates ofone or more of the batteries, ages of one or more of the batteries,numbers of charging cycles the batteries have endured, the temperatureof one or more of the batteries, another factor indicating health orcondition of one or more of the batteries, the quantity of currentavailable from the power source, historical usage patterns of theelectronic device, user preferences, user input, or combinationsthereof. A charge state of a battery may include the current chargelevel as a percentage of the battery's full capacity and may alsoinclude other information indicative of the battery's health orcapabilities. The allocation of the current may be changed when case 930is connected to a new power source and/or to a power source of adifferent capacity. The various factors listed above may also bemonitored on an ongoing or periodic basis during the charging and theallocation of current may be changed based on changing circumstances asindicated by changes in one or more of the factors listed above.

As illustrated in FIG. 9, case 930 may also include one or more datainput device(s). These data input device(s) may include one or more ofswitches, a keypad, a mouse, a trackball, a pointing device, a bar codescanner, a credit card reader, a radio frequency identification (RFID)tag reader, a near field communication (NFC) device, and/or a datareceiving device of another type. In addition, case 930 may include adata output device such as a printer, a radio frequency (RF)transmitter, and/or a memory card.

Power source 1010 may be a docking station that is capable ofsimultaneously charging a plurality of case 1030s. As with other powersources, the docking station may have a maximum current limit it is ableto supply to docked case(s), collectively. In some configurations, thedocking station may command the docked cases to consume no more than aspecified amount of current. For example, if the docking station iscapable of supplying up to 6 A of charging current and four cases arecurrently docked, the docking station may command each of the dockedcases to consume no more than 1.5 A each. If one of the docked cases isthen removed, the docking station may dynamically adjust the limit foreach of the remaining 3 devices up to a maximum of 2 A of current each.In another example, one or more of the docked cases may be given acurrent limit that is higher than the other cases based on a chargestate of one or more of its batteries.

FIG. 10 illustrates a case 1030 interfaced to power source 1010 anddevice 1050 in one embodiment of the techniques disclosed herein. Backshell 215 is an example of case 1030. Some or all of the electricalcomponents of case 1030 may be included on one or more printed circuitboards.

Device 1050 may be a tablet, smartphone, mobile communication device,mobile computing device, portable computer, laptop, or computing deviceof another type. In one specific example, device 1050 is an APPLE IPADused as a mobile point of sale device in a retail shopping environmentin conjunction with case 1030. Device 1050 includes device interface1052, device battery 1053, user interface 1054, and device processor1051. Device processor 1051 may be any type of microcontroller,microprocessor, microcomputer, programmable logic device, reconfigurablecircuit, or application specific circuit that is configured to operatedevice 1050 or a portion of device 1050. Device battery 1053 is arechargeable battery that is integrated within or attached to device1050. User interface 1054 may include a touchscreen, a button, a switch,a keyboard, a pointing device, or a combination thereof, enabling a userto interact with device 1050.

Device interface 1052 provides an electrical interface between device1050 and a cable or device. Device interface 1052 includes electricalconductors for providing power to charge device battery 1053 as well asproviding control and data lines for communicating with device processor1051 or other components of device 1050. In one example, deviceinterface 1052 may comprise an APPLE 30 pin connector. In another case,device interface 1052 may comprise an APPLE LIGHTNING connector. In yetanother example, device interface 1052 may be an industry standardizedconnector or a proprietary connector or interface associated withanother device manufacturer.

Case interface 1032 comprises an electrical and mechanical interfacethat is compatible with and mates with device interface 1052. Caseinterface 1032 enables power and communications to be exchanged betweencase 1030 and device 1050.

In some situations, case interface 1032 may have to meet certainrequirements to be compatible with device 1050. For example, if device1050 is an APPLE IPAD, case interface 1052 may have to meet therequirements of the APPLE Made for IPHONE/IPAD/IPOD (MFI) program. Inaddition, case interface 1032, or some other element of case 1030, mayinclude an authentication chip or other type of electronicauthentication device that may be necessary to establish communicationsbetween case 1030 and device 1050

Case 1030 may be designed and manufactured in variations each having acase interface 1032 that is configured to interface with differentelectronic devices or families of electronic devices. Each variation ofcase 1030 may include a different mechanical, electrical, and/orprotocol interface for interacting with the one or a family ofelectronic devices that are compatible with that particular interface.For example, one implementation of case 1030 may have an interface andprotocol capable of interfacing with a particular generation of IPAD,while another implementation of case 1030 may have an interface capableof interfacing with a tablet made by another manufacturer. In somesituations, case processor 1021 may execute software which is customizedfor a particular electronic device or use parameters that are customizedfor a particular electronic device. If case 1030 is interfaced to anANDROID-based computing device, case interface 1032 may have to becompliant with ANDROID Open Accessory protocol, or a similar protocol,for detecting and setting up communication between case 1030 and thecomputing device.

Device 1050 will typically have many components in addition to thosethat are illustrated in FIG. 10, such as a display and/or communicationcomponents. For purposes of clarity, only those components of device1050 that are most pertinent to the techniques and apparatuses describedherein are illustrated in device 1050. However, it should be understoodthat the techniques and apparatuses described herein are not to belimited to any particular type or configuration of electronic device.

Power source 1010 comprises any source of power for charging case 1030and/or device 1050. Power source 1010 could be a charger compatibledevice 1050 that is plugged into a wall outlet, an automobile chargerfor device 1050, a custom charging stand, a USB port, or any other typeof electrical device that provides current at a designated voltage or ina designated voltage range. In some situations, power source 1010 may beintegrated into another device, such as a USB port in a computer. Powersource 1010 may be connected to case 1030 using a cable such as cable230.

Case 1030 includes case processor 1021, battery charger 1022, casebattery 1023, battery monitor 1024, voltage controller 1025, userinterface 1026, display driver 1027, display 1028, credit card reader1035, bar code scanner 1036, current limiter 1029, case power connector1031, and case interface 1032. Case processor 1021 is an example ofprocessor 921. Battery charger 1022 is an example of battery charger922. Battery 220 is an example of case battery 1023. Battery monitor1024 is an example of battery monitor 924. Current limiter 1029 is anexample of current control module 929. Credit card reader 1035 and barcode scanner 1036 are examples of data input device(s) 933. In additionto the functions described below, case 1030 also provides physicalprotection to device 1050. Physical protection may include protectionfrom the effects of impact, shock, scratching, puncture, liquids, dust,sunlight, or other forces which could potentially damage or affect theoperation of device 1050. In some configurations, case battery 1023 maybe external to case 1030 and case 1030 may include one or moreinterfaces or slots capable of providing an interconnection to one ormore external batteries similar to case battery 1023.

Case power connector 1031 is any type of electromechanical connectorthat allows power source 1010 to be electrically interconnected to case1030. Case power connector 1031 may comprise a USB connector, a mini USBconnector, a micro USB connector, a cylindrical connector, or aconnector of another type, including combinations thereof. Case powerconnector 1031 may also include conductors for communication and/ortransfer of data enabling power source 1010, or another device, tocommunicate with case processor 1021. Port 1705 is an example of casepower connector 1031.

In some situations, case power connector 1031 may support otherfunctions when not connected to a power source. For example, case powerconnector 1031 may also be configured to support communication betweendevice 1050 and an input device or peripheral such as: an externalkeyboard, a mouse, a display, a GPS device, a mobile phone, asmartphone, a computing device, or a combination thereof. In some cases,in addition supporting the communication between one or more of theseinput or peripheral devices and device 1050, case 1030 may also supplypower to one or more of these devices through case power connector 1031.As described above with respect to FIG. 9, case 1030 may also havemultiple power connectors in different mechanical and/or electricalconfigurations. In some configurations, the multiple power connectorsmay be configured for different current levels.

Display 1028 comprises any device for visually conveying information toa user of case 1030 and/or device 1050. Display 1028 may include one ormore of: a light emitting diode (LED), an organic light emitting diode(OLED), a liquid crystal display (LCD), electronic paper,electrophoretic ink, another type of device for visually conveyinginformation to a user, or combination thereof.

Display 1028 may be used to convey to a user information about case 1030and/or device 1050 including: a state or mode of case 1030, a state ormode of device 1050, a charge level of case battery 1023, a charge levelof device battery 1053, and/or a combined charge level of case battery1023 and device battery 1053. Display driver 1027 is a device forcontrolling, operating, driving, and/or managing the one or moreelements which make up display 1028. User interface 1026 is any type ofdevice for receiving an input or a selection from a user of case 1030.User interface 1026 may include a switch, a button, a group of switchesor buttons, a touchscreen, a proximity sensor, a keyboard, a keypad, amouse, a trackball, a touchpad, a joystick, or a combination thereof.Buttons are examples of user interface 1026. In some configurations,user interface 1026 may be an interface to an external user interfacedevice that is not contained within or part of case 1030.

User interface 1026 may also be used for purposes other than activatingdisplay 1029. In one example, a user may hold down a switch associatedwith user interface 1026 for a predetermined number of seconds in orderto reset case processor 1021 and/or other components of case 1030. Inanother example, one or more switches that make up user interface 1026may be pressed in a predetermined pattern or sequence to change anoperating mode of case processor 1021 and/or case 1030. Inputs to userinterface 1026 may also be used to provide inputs to and/or change anoperating mode of device 1050. Display 1028 may also be used to displayinformation relating to the input of data through user interface 1026.For example, if user interface 1026 includes one or more switches whichare used to select from among various settings or menu choices, LEDswhich make up display 1028 may be used to indicate a menu item, aselection of a setting, and/or a current state of a menu item orsetting.

Many other types of input devices and display devices are known in theart and may be used to implement user interface 1026 and/or display1028. The apparatuses, solutions, and techniques disclosed herein arenot to be limited to any specific type of user input device, userinterface, display device, method of receiving input from a user, ormethod of displaying information to a user.

Credit card reader 1035 is any device for reading a credit card, debitcard, pre-paid card, gift card, or other type of payment device. Creditcard reader 1035 may read a magnetic strip of a payment device and/ormay read payment device information through RF communication with thepayment device.

Bar code scanner 1036 is any device for reading product identifyingdata, such as a Universal Product Code (UPC), from an object. Bar codescanner 1036 may include a laser that is swept across a bar code or mayread information from a product using electronic or RF communication, asis done when reading and RFID tag that is on or within a product.

Voltage controller 1025 is a device for adjusting the voltage of poweroutput by case battery 1023 to device 1052. In one example, case battery1023 and device battery 1053 are both 3.7 volt (3.7V) batteries. In thisexample, case 1030 is designed to receive power at 5 volts (5V) becausesome common interfaces (i.e., USB) are specified to provide power at 5V.Consequently, device 1050 may also be configured to receive power at 5Vwith that voltage being internally stepped down in device 1050 (notshown) before it is applied to device battery 1053. When charging casebattery 1023, battery charger 1022, or another voltage regulation oradjustment device, steps down the 5V received from power source 1010 toan appropriate voltage for charging case battery 1023. Even though, inthis example, case battery 1023 and device battery 1053 are both 3.7Vbatteries, current provided from case battery 1023 to device battery1053 must be stepped up to 5V by voltage controller 1025 because 5V isexpected at device interface 1052 and device 1050 has been otherwisedesigned to use current supplied at 5V to charge device battery 1053.Many other combinations of voltages are possible.

In addition to adjusting the voltage output from case 1030 to device1050, voltage controller 1025 may also perform a switching function forthe power delivered from case battery 1023 to device 1050. For example,depending on a selected charge profile and the states of case battery1023 and device battery 1053, it may be desirable to prohibit currentflow from case battery 1023 to device 1050 in some circumstances. Forexample, even though device battery 1053 is not at 100% charge and case1030 is not connected to power source 1010, case 1030 may not deliverpower from case battery 1023 to device 1050 until the charge level ofdevice battery 1053 drops below a specified level (i.e., device battery1053 drops below 60% charge).

In addition to stepping voltage up and/or down, voltage controller 1025may also perform this switching function under the control of caseprocessor 1021. Alternately, the switching function may be performed bya component of case 1030 separate from voltage controller 1025.

In addition to supplying power to device 1050, case 1030 communicateswith device 1050 using case interface 1032 and device interface 1052.This communication may be used to manage and/or control various powerand battery charging related functions and/or exchange data for otherpurposes. While the communication between case 1030 and device interface1052 is illustrated as being conducted using the same interface and/orconnector that is used to supply power to device 1050, it should beunderstood that this communication may also occur using a differentinterface and/or connector than is used to supply power from case 1030to device 1050. Communication between case 1030 and device 1050 mayoccur through one or more different communication methods and/orprotocols. For example, communication between case 1030 and device 1050may occur using a wired connection, a wireless link, near fieldcommunication, magnetic communication, inductive communication, lightwave communication, infrared communication, audio frequencycommunication, or a combination thereof.

Communication between case 1030 and device 1050 may be automaticallyestablished when they are connected or may be established only whencommunication between case 1030 and device 1050 is necessary. As usedherein, the term ‘communication’ is intended to mean communicating dataor information. ‘Communication’ is not intended to include the supplyingof power from one device to another. In some situations, case 1030 mayinterface to case 1050 in multiple ways. For example, case 1030 maytransfer power to and communicate with an IPAD using an APPLE 30 pin orLIGHTNING connector. In other situations, one connector may be used totransfer power from case 1030 to device 1050 while data communicationsbetween them occur through another connector (for example, through aheadphone or microphone port) on device 1050.

In addition to the methods discussed above for controlling how muchcurrent an electronic device is permitted to consume, case 1030 may alsocommand or direct device 1050 to use no more than a specified amount ofcurrent by sending a command or instruction using one or more of thecommunication methods described above. In some situations, case 1030 maysend a command to device 1050, or another similar device such aselectronic device 205, directing the device to consume a specifiedamount, or no more than a specified amount, of current. This command maybe issued in the form of a specific current limit (i.e., 350 mA) or maybe a selection of one of a small number of pre-defined charging levels(i.e., charging level 2 of 4).

In one example, even though device 1050 may be capable of consuming upto 750 mA of current, case 1030 may send a command, or other type ofcommunication, to device 1050 instructing it to limit consumption to alesser amount, 400 mA for example. This type of command may be used tolimit the current consumed by device 1050 rather than by limiting itusing current limiter 1029 or current control module 929 as described inprevious examples. Existing electronic device case solutions do notprovide a means of performing these types of communications between acase and the associated electronic device. Therefore, existing solutionsdo not provide these types of intelligent charging and power managementfeatures between a case and the associated electronic device.

Case 1030 may issue a command or use other communication with device1050 to limit current to device 1050 for a number of reasons. In oneexample, case 1030 may limit the current to device 1050 in order topreserve some current for charging case battery 1023. In anotherexample, case 1030 may limit current to device 1050 in order to protectpower source 1010 from being overburdened. In another example, case 1030may limit current to device 1050 in order to synchronize the charging ofdevice battery 1053 and case battery 1023 such that they will both befinished charging at approximately the same time. This may includeongoing monitoring of the state of the two batteries and periodicadjustment of how current is allocated between the two in order todynamically compensate for their changing states and/or charging rates.In another example, case 1030 may limit current to device 1050 forthermal management purposes. Case 1030 may limit the current in order tomanage a temperature of device 1050, a temperature of a component ofdevice 1050, a temperature of case 1030, a temperature of a component ofcase 1030, a temperature of power source 1010, or a combination thereof.

Case 1030 may also allocate current between itself and device 1050 basedon how much current device 1050 is currently consuming. If device 1050is currently in an active operational mode and consuming a relativelylarge amount of current, case 1030 may allocate a larger portion of thecurrent available from power source 1010 to counterbalance the effectsof device battery 1053 being depleted at a relatively high rate due tothe operation of device 1050. The allocation may be dynamically adjustedbased on how the electronic device is being used.

In some situations, case 1030 may control the allocation of currentbetween case 1030 and device 1050 in accordance with a usage profile. Ausage profile may be a default profile programmed into case 1030 or maybe a set of user-defined or user-modified parameters. For example, ausage profile may indicate that a user always wishes for device battery1053 to be fully charged before the charging of case battery 1023begins. This configuration is convenient for a use model in which device1050 is sometimes used without case 1030 because device battery 1053will always have the maximum possible charge, relative to case battery1023. If device 1050 is disconnected from case 1030 and used independentof case 1030 for a period of time, it may potentially be used for alonger period of time in this mode because the charging of devicebattery 1053 has been prioritized.

Because batteries may charge more efficiently or effectively whencharged more slowly, case 1030 may also limit the amount of currentallocated to case battery 1023 and/or device 1050 in order to accomplisha slower or more gradual charge cycle for one or more of the batteries,rather than using a larger amount of the available current to charge thebatteries serially in time (i.e., direct all or most the availablecurrent to charge one of the batteries first and then divert the currentto the second battery when the first is fully or nearly fully charged).When charged in this manner, case 1030 may be supplying less current todevice 1050 than device 1050 would consume if connected directly to apower source.

In some situations, the slow charging approach described above may alsoinvolve communication between case 1030 and device 1050 regarding whattype of charge cycle or charge mode is being used or is planned to beused. In one example, case 1030 may communicate with device 1050 toobtain information about device battery 1053 or preferred chargingcharacteristics for device battery 1053. The selection of a chargingmode may also be based on a usage profile, a user profile, a type ofpower source 1010, a capacity of power source, 1010, or a combinationthereof.

Case 1030 may also adjust the allocation of current to device 1050 basedon the operational mode of device 1050. If device 1050 is operationaland consuming current, case 1030 may allocate more current to device1050 in order to provide current for device 1050 to operate as well asto charge device battery 1053. For example, it may be desirable tocharge device battery 1053 using 500 mA of current. Case 1030 mayprovide 500 mA of current for this purpose, or may command device 1050to only draw 500 mA, when device 1050 is in a standby, low power, orhibernate mode. However, if device 1050 is active and is consuming morepower, case 1030 may change the allocation of current to device 1050 inorder to accommodate the power usage of device 1050 while maintainingthe charging of device battery 1053 at approximately the same rate as ithad been charging when device 1050 was in standby, low power, orhibernate mode. In other words, case 1030 may adjust the amount ofcurrent supplied to device 1050 in order to keep the amount of currentavailable for charging of device battery 1053 roughly constant while theoperational mode of device 1050 is changing. Case 1030 may receiveinformation about the operating mode of device 1050 throughcommunication with device 1050 using one of the methods described above,by monitoring current consumption of device 1050, or by other means. Insome configurations, rather measuring the current consumed by device1050, device 1050 may measure its own power consumption and provide thisinformation to case 1030.

Case 1030 may also provide improved power management functions whenattached to device 1050 with respect to the use or discharge of casebattery 1023 and/or device battery 1053. Existing solutions may fully,or nearly fully, discharge one battery before use of the other begins.However, some types of batteries operate more efficiently (i.e., canprovide more total power over time) when discharged more slowly.Consequently, using case battery 1023 and device battery 1053 tojointly, simultaneously satisfy the current needs of device 1050 mayeffectively increase the amount of power available from the twobatteries thereby increasing the time that device 1050 can be usedbefore recharging is necessary. In order to properly manage simultaneousbattery use or discharge, case 1030 may communicate with device 1050using one of the previously described methods to obtain informationregarding one or more of the following: the current charge state ofdevice battery 1053, a rate of current usage from device battery 1053 bydevice 1050, a total rate of current usage by device 1050, anoperational mode of device 1050, or a combination thereof.

In some situations, case 1030 may toggle between the various chargingand discharging operations modes described above based on a time of dayand/or a day of week. For example, device 1050 may be used more heavilyduring daytime and evening hours and more infrequently during nighthours. Therefore, case 1030 may allocate available current from powersource 1010 to case battery 1023 and device 1050 differently duringthese various periods. During nighttime hours, it may be more likelythat power source 1010 will remain connected for a longer period oftime. Therefore, during these periods it may be more efficient tosimultaneously charge both batteries and/or charge one or more of thebatteries using a lower charging current (i.e., a slower charge rate).This may result in a more complete charge while having little effect onflexibility because it is more likely case 1030 will remain connected topower source 1010 for a long enough time period to fully charge bothbatteries. Case 1030 may access a clock, calendar, or other scheduleinformation on device 1050 to make charging profile determinations.

In some situations, it may be beneficial to charge device battery 1053at a lower charging rate when it is near, or as it nears, full capacity.Consequently, case 1030 may determine a charging rate or chargingcurrent level such that it has an inverse relationship to the chargestate, or percentage of full capacity, of the device battery 1053. Thecharging rate may be periodically adjusted as device battery 1053 and/orcase battery 1023 are charged.

Case 1030 may also include capabilities to monitor its own power leveland perform mode changes accordingly. In one example, case 1030 isconnected to device 1050 but is not connected to power source 1010. Case1030 monitors the level of case battery 1023 and deactivates or shutsdown case 1030 when the level of case battery 1023 drops below apredetermined level. Case 1030 may be put into a sleep or hibernate modeor may be shut down entirely. In this way, device 1050 will no longerattempt to draw current from or communicate with case 1030 and device1050 may operate, at least temporarily, as if it is not attached to case1030 even though it may remain physically attached to case 1030.

A software application may be run on device processor 1051 of device1050 to monitor, configure, or view data associated with the variouscharging and power management features described herein. The softwareapplication may reside on case 1030 and be loaded from case 1030 todevice 1050 when device 1050 is attached to case 1030. Alternately, case1030 may provide instructions to device 1050 directing device 1050 toobtain the software application from another location. For example, whenconnected to device 1050, case 1030 may provide a universal resourcelocator (URL) to device 1050 that device 1050 can use to download to theapplication from a website or a server associated with the URL. The URLmay also be associated with a manufacturer or supplier of device 1050, amanufacturer or supplier of case 1030, or an application store ordownload site from which the software application may be downloaded.

In addition to the types of information described above, case 1030 mayalso provide other types of information to device 1050 or to a softwareapplication running on device 1050. For example, case 1030 may transmitone or more messages to device 1050 that include information such as: anindication that the supply of power from case 1030 to device 1050 isabout to be cut, an indication that the level of current from case 1030to device 1050 is about to be changed, information about power source1010, and/or a status of case 1030.

Case 1030 may also communicate with other devices or systems using thecommunication capabilities of device 1050. For example, case 1030 maytransmit a request to device 1050, or a software application running ondevice 1050. Then, the request is transmitted to a recipient by device1050, such as to a server over a wireless communication network. Device1050 may receive a response to the request and transmit that response tocase 1030. In one example, the request may be for a firmware update forcase 1030 and the response may include the firmware update.

In another example, historical charging and device usage information maybe collected by case 1030 and/or device 1050 and transmitted to arecipient for analysis. Based on the historical information, therecipient may provide a new recommended charging profile, pattern, oralgorithm that better suits that user's behaviors and usage patterns.Case 1030 receives, via device 1050, the new recommended chargingprofile, pattern, or algorithm and substitutes it for the previous one.In this way, case 1030 can optimize the charging algorithm for each userbased on their actual usage patterns.

The software application may communicate with case 1030 in a variety ofways. In one example, the software application, running on deviceprocessor 1051, may communicate with case 1030 using device interface1052. In another example, the software application may communicatedirectly only with device 1050 and rely on software or firmwarecontained in device 1050 to relay messages to or perform communicationswith case 1030.

In the situation where device 150 is a device designed or manufacturedby APPLE, a software application running on device 1050 may communicatewith case 1030 using the APPLE external accessory framework. Theexternal accessory framework provides a conduit for communicatingbetween APPLE devices and attached accessories. This conduit may be usedto integrate accessory level features into software applications.Features or functions of case 1030 can be integrated into a softwareapplication, if any, running on case 1030 using this framework.

Communicating with an external accessory typically requires workingclosely with the accessory manufacturer to understand the servicesprovided by that accessory. Manufacturers must build explicit supportinto their accessory hardware for communicating with iOS. As part ofthis support, an accessory must support at least one command protocol,which is a custom scheme for sending data back and forth between theaccessory and an attached app.

In one example, the software application may be configured to displayone or more of many different types of information for each batteryincluding: battery type, battery capacity, current battery charge level,battery age, battery health, and number of charge/discharge cycles. Inaddition, the software application may also determine a power remainingmetric, based on the charge remaining in each of the batteries, anddisplay an estimated amount of operation time remaining for device 1050based on the power remaining metric. The time remaining may be expressedas a percentage (i.e., 30% remaining) or as an amount of time (i.e., 2hours and 45 minutes). The estimated amount of time remaining may bebased on tracking how much power has been used over a recent period oftime, a current operating mode of device 1050, other battery lifeprediction methods, battery health, or a combination thereof. The timeremaining may be expressed as a combined figure which takes bothbatteries into account but also conveys how much of that total isprovided by each of two or more batteries

Transaction processing software may also be executed on device 1050 bydevice processor 1051 to perform various POS-related functions. Forexample, the transaction software may communicate with case processor1021 to receive information about the various products scanned by barcode scanner 1036. The software may also perform various functions suchas generating a total purchase price for the scanned products, computingsales tax, and/or communicating the payment information to a paymentprocessing system. User inputs for navigating the transaction softwaremay be received at user interface 1054 of device 1050 and/or userinterface 1026 of case 1030. In one example, the menus of thetransaction software may be navigated through one or more switches onthe bottom of case 1030 as illustrated in FIG. 3. A user may use theseswitches to navigate the menus of the transaction software using asingle hand. In one variation, rather than switches, case 1030 mayinclude a touch pressure sensitive mouse pad or other pointing device onthe bottom of case 1030 that the user operates using one or more fingersof the hand holding case 1030.

Using credit card reader 1035 and bar code scanner 1036, device 1050 maybe used as a mobile point of sale terminal in a retail or other businessenvironment. Device 1050, in conjunction with case 1030, can be carriedaround a store for scanning various products of interest. When all ofthe products of interest have been selected and scanned, paymentinformation may be obtained using credit card reader 1035. One or moresoftware applications running on device processor 1051 may be used tofacilitate the transaction processes described above. In addition tousing device 1050 and case 1030 as a POS terminal, the combined devicemay also be used for other mobile information processing purposes suchas conducting inventory, filling orders in a warehouse, gathering fielddata, or taking orders at a restaurant.

Case 1030 may also include a solar cell or other alternate type of powersource. A solar cell can be used to supplement the power needed tooperate device 1050 and charge one or more of the batteries when case1030 is exposed to light of a sufficient intensity to generate currentfrom the solar cell. Case processor 1021, in conjunction with currentlimiter 1029, may be configured to allocate current from the solar cellamong case 1030 and device 1050. When power source 1010 is connected tocase 1030, case 1030 may perform these processes with respect to thecombined current available from power source 1010 and the solar cell.

In another variation of the apparatuses and techniques described herein,bar code scanner 1036 may be a wand, pen, or other handheld scanner (notshown) that docks in case 1030 and can be removed by the user to scanproducts. This allows a user to hold or carry case 1030 in one hand andscan products using the wand held in the other hand. This minimizes theamount of movement the user must perform with case 1030 itself. The wandmay communicate, including wirelessly, with case 1030 and/or device1050. When docked in case 1030, circuitry associated with a rechargeablebattery of the wand may be electrically interconnected to the batterycharging circuitry of case 1030. The current limiting and allocationprocesses described herein with respect to case battery 1023 and devicebattery 1053 may also accommodate the battery of the wand in similarmanners.

In addition to using WiFi and Bluetooth for communications, somecomputing devices also use near field communication (NFC). NFC isdefined by a set of standards for radio frequency (RF) communicationbetween two devices. NFC is related to radio-frequency identification(RFID) standards. Typically NFC enabled devices are able to communicatewith each other after bringing them in close proximity (i.e., a fewcentimeters) of each other. In some situations, NFC communications maybe used to set up or bootstrap a faster and/or more complexcommunication channel.

Case 1030 may also include one or more sensors for detectingenvironmental or handling conditions associated with case 1030. Forexample, case 1030 may include an accelerometer or temperature sensor totrack whether case 1030 has been dropped, subject to impact, or exposedto an area that was either too hot or too cold. This information may beused for determining a warranty status of case 1030 and/or device 1050.

FIG. 11 illustrates a method of operating a case for an electronicdevice in one embodiment of the techniques disclosed herein. In step1110 of FIG. 11, an electrical current is received at a case for anelectronic device from a power source connected to the case. In step1120, the received electrical current is distributed between arechargeable battery in the case and the electronic device based oninformation received by the case through communication with theelectronic device. The communication may involve transmittinginformation or data to the electronic device and/or receivinginformation or data from the electronic device.

FIG. 12 illustrates a method of operating a case for an electronicdevice in one embodiment of the techniques disclosed herein. In step1210, an amount of current available from a power source is determined.In step 1220, a current control limit is set. In some situations, thecurrent control limit is set based on the determined available current.At step 1230, a distribution of the current is determined among anelectronic device and the case for the electronic device based ondistribution factors. These distribution factors may include: a chargestate of a battery in the case, a charge state of a battery in theelectronic device, a capacity of one or both batteries, a charge rate ofone or both batteries, an age of one or both batteries, numbers ofcharging cycles the batteries have endured, a temperature of one or bothbatteries, another factor indicating health or condition of one or bothbatteries, the quantity of current available from the power source,historical usage patterns of the electronic device, user preferences,user input, or combinations thereof.

In step 1240 of the method of FIG. 12, the current is distributed basedon the determined distribution. In some situations, after current hasbeen allocated or distributed to the electronic device, all of theremaining available current from the power source is distributed to thecase and/or the case battery. In other situations, the total currentconsumed from the power source by the case, the electronic device, andany batteries being charged is less than the available current from thepower source.

In step 1250 of the method of FIG. 12, a determination is made as towhether the case has been connected to a new power source. If it isconnect to a new power source, the method returns to step 1210 and adetermination is made regarding how much current is available from thenew power source. If the case has not been connected to a new powersource, the distribution factors continue to be monitored at step 1260.The distribution of current between the case and the electronic devicemay be dynamically adjusted as conditions change.

When a case is configured to charge a case battery and provide power tothe electronic device simultaneously, a profile may indicate that boththe case battery and a battery of the electronic device are to becharged simultaneously with a preference that they are charged at ratessuch that they reach full charge at approximately the same time. At thestart of charging, the electronic device battery may be 5% full and thecase battery 30% full. At the start of charging, based on thedistribution factors, 75% of the available charging current may beallocated to charging the electronic device battery while the remaining25% is allocated to charging the case battery. However, after time, theelectronic device battery may be at 90% charge while the case batteryhas only reached 75%. In this situation, the allocation may bedynamically adjusted to divert more of the available current to the casebattery.

FIG. 13 illustrates computer system 1300 with which some embodiments ofthe techniques disclosed herein may be utilized. Some or all of thesteps and operations associated with the techniques introduced here maybe performed by hardware components or may be embodied inmachine-executable instructions that cause a general purpose or specialpurpose computer processor programmed with the instructions to performthe steps. Alternatively, the steps may be performed by a combination ofhardware, software, and/or firmware. According to the example of FIG.13, computer system 1300 includes a bus 1390, at least one computerprocessor 1310, at least one communication interface 1330, at least onememory 1320, at least one mass storage 1340, and at least one powerinterface 1350. A removable storage media 1360 also interface to bus1390 of computer system 1300.

Computer processor 1310 can be any known computer processor, centralprocessing unit, microprocessor, microcontroller, programmable logicarray, or programmable logic device. Computer processor 1310 may alsointerface to a coprocessor.

Communication interface 1330 can be any type of interface forcommunicating with another device or a network. Communication interface1330 may be configured for communicating using a wired connection, awireless connection, audio signals, light waves, infrared, or acombination thereof. Communication interface 1330 may be configured forcommunicating with or over a network such a Local Area Network (LAN),Wide Area Network (WAN), or any network to which computer system 1300connects. Communication interface 1330 may also be configured tocommunicate with an electronic device such as a cellular phone, asmartphone, a tablet, a laptop computer, a server, or a digital audiodevice. The various functions of communication interface 1330 may bedistributed across multiple communication interfaces. In one example,communication interface 1330 is a USB interface.

Memory 1320 can include random access memory (RAM), or any other type ofdynamic data storage device commonly known in the art. Memory 1320 mayalso include one or more static storage devices such as read only memory(ROM), programmable read only memory (PROM), flash memory, magneticmemory, erasable programmable read only memory (EPROM), and/orelectrically erasable programmable read only memory (EEPROM) for storingstatic data such as firmware or machine-executable instructions forcomputer processor 1310 or for another computer processor. In someconfigurations, memory 1320 may be contained within computer processor1320 or within another device of computer system 1300.

Mass storage 1340 can include one or more persistent mass data storagedevices or modules that may be used to store data, information, and/orinstructions. Mass storage 1340 may include a hard drive, a tape drive,an optical drive, flash memory, a micro electromechanical storagedevice, or a combination thereof.

Power interface 1350 can be any type of interface for receiving and/ortransmitting electrical power. The functions of power interface 1350 maybe spread across multiple power interfaces. The functions of powerinterface 1350 may also be combined into a single connector and/orinterface with communication interface 1330. For example, the functionsof communication interface 1330 and power interface 1350 may both beimplemented in the form of one or more USB interfaces.

Removable storage media 1360 can be any kind of external data storagedevice including a hard drive, a memory card, a subscriber identitymodule (SIM) card, flash memory, an optical drive, a tape drive, a microelectromechanical storage device, or a combination thereof.

Bus 1390 communicatively couples the elements of computer system 1300,as well as removable storage media 1360. Bus 1390 may conform to anindustry standard bus architecture and protocol or may use a proprietaryarchitecture and/or protocol.

In one example, a case for an electronic device can include an interfaceto a battery, an interface to receive electrical power from an externalpower source, a payment device reader, a product information inputdevice, and a computer processor. The computer processor can beconfigured to execute computer-readable instructions to limit an amountof current of the received electrical power used by each of the case andthe electronic device, read product information from a product using theproduct information input device, and read information from a paymentdevice using the payment device reader. The step of limiting the amountof current can include detecting a type of the external power source anddetermining a current limit for the power source based on the type ofthe external power source. The step of limiting the amount of currentcan include allocating the amount of current among the case and theelectronic device based on a state of the electronic device. The stateof the electronic device can include one or more of: a charge level of abattery of the electronic device and an operational mode of theelectronic device. The state of the electronic device can be received bythe case through communications with the electronic device. The step ofallocating can include allocating using a charging profile that is basedon one or more of: a charge level of the battery, a charge level of abattery of the electronic device, an amount of current available fromthe external power source, and a user preference received from theelectronic device. The step of limiting the amount of current caninclude transmitting a command to the electronic device instructing theelectronic device to use no more than a specified amount of current. Theproduct information can be a bar code, and the product information inputdevice can be a bar code reader. The payment device reader can be amagnetic strip reader for reading a magnetic strip of a credit card orof a debit card.

In one example, a method of performing power management in a case for amobile computing device can include limiting electrical current receivedat the case to a current limit where the electrical current is receivedfrom a power source connected to the case, commanding the computingdevice to consume no more than a specified amount of the receivedelectrical current, monitoring an amount of the electrical currentconsumed by the computing device, and distributing a balance of thecurrent limit not consumed by the computing device to components of thecase, wherein the components of the case include a rechargeable battery,a payment card reader, and a bar code scanner. The method can includedetermining the current limit based on a characteristic of the powersource. The method can include determining the current limit based on atype of connection used to interface to the power source. The step ofcommanding the computing device to consume no more than a specifiedamount of the received electrical current can include receivinginformation from the computing device indicating one or more of: acharge state of a battery of the computing device and an operationalmode of the computing device.

In one example, a charging station can include docking locations for aplurality of electronic devices and a charge control circuitry. Thecharge control circuitry can be configured to determine a number of theelectronic devices docked in the docking locations, determine availablecurrent, determine an allocation of the available current for each ofthe electronic devices docked in the charging station based on theavailable current and the number of the electronic devices, and limitcurrent consumption of each of the electronic devices based on theallocation. Allocation of the available current for each dockedelectronic device can be equal to the allocation of the availablecurrent for each of the other docked electronic devices. Determining anallocation of the available current for each docked electronic devicecan be further based on a charge level of a battery of that electronicdevice. The step of limiting current consumption by each dockedelectronic device can include limiting an amount of current available toeach docked electronic device based on the allocation. The step oflimiting current consumption by each docked electronic device caninclude transmitting a command to one or more of the docked electronicdevices, where the command includes an instruction to limit currentconsumption.

The components described above are meant to exemplify some types ofpossibilities. In no way should the aforementioned examples limit thescope of the invention, as they are only exemplary embodiments.

The foregoing disclosure has been presented for purposes of illustrationand description. Other modifications and variations may be possible inview of the above teachings. The embodiments described in the foregoingdisclosure were chosen to explain the principles of the concept and itspractical application to enable others skilled in the art to bestutilize the invention. It is intended that the claims be construed toinclude other alternative embodiments of the invention except as limitedby the prior art.

The phrases “in some embodiments,” “according to some embodiments,” “inthe embodiments shown,” “in other embodiments,” “in some examples,” “insome cases,” “in some situations,” “in one configuration,” “in anotherconfiguration” and the like generally mean that the particular feature,structure, or characteristic following the phrase is included in atleast one embodiment of the present invention and/or may be included inmore than one embodiment of the present invention. In addition, suchphrases do not necessarily refer to the same embodiments or differentembodiments.

What is claimed is:
 1. A protective cover for a mobile computing devicehaving a touchscreen, the protective cover comprising: a shell to atleast partially surround the mobile computing device when the mobilecomputing device is installed in the shell, the shell having an outersurface and an inner surface, the shell providing access to thetouchscreen of the installed mobile computing device; a rechargeableenergy storage device; a first electrical connector accessible at theouter surface of the shell for temporarily electrically interconnectingthe protective cover to an external power supply for receivingelectrical power from the external power supply; a second electricalconnector attached to the inner surface of the shell for electricallyinterconnecting the protective cover to the installed mobile computingdevice; and electrical circuitry configured such that: when theprotective cover is receiving the electrical power from the externalpower supply through the first electrical connector, the electricalcircuitry distributes the received electrical power to the installedmobile computing device through the second electrical connector and tothe rechargeable energy storage device of the protective cover to chargethe rechargeable energy storage device; and when the protective cover isnot receiving the electrical power from the external power supply, theelectrical circuitry distributes stored electrical power from therechargeable energy storage device of the protective cover to theinstalled mobile computing device through the second electricalconnector, wherein the distribution of the stored electrical power tothe installed mobile computing device occurs only after receiving a datacommunication from the mobile computing device, and wherein thedistribution is based on information included in the data communicationreceived from the mobile computing device.
 2. The protective cover ofclaim 1 wherein the rechargeable energy storage device includes arechargeable battery.
 3. The protective cover of claim 1 furthercomprising a speaker opening to accommodate a speaker of the installedmobile computing device.
 4. The protective cover of claim 1 wherein thedata communication from the mobile computing device is received throughthe second electrical connector.
 5. The protective cover of claim 1wherein the data communication from the mobile computing device isreceived wirelessly.
 6. A protective case for an electronic devicehaving a touchscreen interface, the protective case comprising: aprotective shell to at least partially enclose the electronic devicewhen the electronic device is installed in the protective shell, theprotective shell having an outer surface and an inner surface, theprotective shell permitting access to the touchscreen interface of theinstalled electronic device; a first electrical connector at the outersurface of the protective shell for electrically connecting theprotective case to an external power source and for receiving electricalpower from the external power source when the external power source iselectrically connected to the protective case through the firstelectrical connector; a second electrical connector at the inner surfaceof the protective shell for electrically connecting the protective caseto the installed electronic device; a rechargeable battery; and acomputer processor configured for: distributing a first portion of thereceived electrical power to the installed electronic device through thesecond electrical connector and distributing a second portion of thereceived electrical power to the rechargeable battery of the protectivecase; and distributing stored electrical power from the rechargeablebattery of the protective case to the installed electronic devicethrough the second electrical connector when the protective case is notconnected to the external power source, wherein distributing the storedelectrical power to the installed electronic device is based oninformation indicating an operational mode of the installed electronicdevice, the information received before the distributing of the storedelectrical power to the installed electronic device.
 7. The protectivecase of claim 6 further comprising a memory storing non-transitorycomputer-executable instructions for execution by the computer processorto perform the distributing.
 8. The protective case of claim 6 furthercomprising a transparent membrane that covers the touchscreen interfaceof the installed electronic device, protects the touchscreen interfaceof the installed electronic device, and enables operation of thetouchscreen interface by a user through the transparent membrane.
 9. Theprotective case of claim 6 further comprising a plurality of lightemitting diodes controlled by the computer processor for indicating astate of the rechargeable battery of the protective case.
 10. Theprotective case of claim 6 wherein the protective case exchanges datacommunications with the installed electronic device through the secondelectrical connector and the operational mode of the electronic deviceis determined based, at least in part, on the data communications.
 11. Aprotective case for an electronic device having a touchscreen interface,the protective case comprising: a cover that at least partiallysurrounds the electronic device when the electronic device is installedin the protective case, the cover having an outer surface and an innersurface, the cover permitting access to the touchscreen interface of theinstalled electronic device; a rechargeable battery; a first electricalconnector accessible at the outer surface of the cover for electricallyconnecting the protective case to an external power source and forreceiving electrical power from the external power source when theexternal power source is electrically connected to the protective casethrough the first electrical connector; a second electrical connectoraccessible at the inner surface of the cover for electrically connectingthe protective case to the installed electronic device; and electricalcircuitry to: distribute a first portion of the received electricalpower to the installed electronic device through the second electricalconnector and distribute a second portion of the received electricalpower to the rechargeable battery of the protective case when theprotective case is connected to the external power source; anddistribute stored electrical power from the rechargeable battery of theprotective case to the installed electronic device through the secondelectrical connector when the protective case is not connected to theexternal power source, wherein the stored electrical power isdistributed to the installed electronic device only after receiving anelectrical signal at the electrical circuitry from the installedelectronic device.
 12. The protective case of claim 11 wherein theelectrical circuitry is further configured to: determine a current limitfor the external power source based on a characteristic of the externalpower source; and limit the received electrical power based on thecurrent limit.
 13. The protective case of claim 12 wherein theelectrical circuitry is further configured to determine thecharacteristic of the power source.
 14. The protective case of claim 11wherein the electrical circuitry is further configured to: determine acurrent limit for the external power source based on a characteristic ofthe electrical connection to the external power source; and limit thereceived electrical power based on the determined current limit.
 15. Theprotective case of claim 11 wherein the electrical signal is receivedfrom the electronic device.
 16. The protective case of claim 11 whereinthe cover comprises a first case portion that is removably attachable toa second case portion to at least partially surround the electronicdevice.
 17. The protective case of claim 11 wherein the first electricalconnector includes one of a mini USB connector and a micro USBconnector.
 18. The protective case of claim 11 wherein to distribute thefirst portion of the received electrical power to the installedelectronic device through the second electrical connector and distributethe second portion of the received electrical power to the rechargeablebattery of the protective case includes to: monitor an amount of thereceived electrical power consumed by the installed electronic device;and distribute at least a portion of the received electrical power notconsumed by the installed electronic device to the rechargeable batteryof the protective case.
 19. The protective case of claim 11 furthercomprising a flexible transparent membrane that extends over thetouchscreen interface of the installed electronic device and allowsoperation of the touchscreen interface through the flexible transparentmembrane.
 20. The protective case of claim 11 further comprising one ormore display elements for indicating a charge state of the rechargeablebattery of the protective case.